Stockholders' Equity - Additional Detail (Details) - USD ($)	3 Months Ended	9 Months Ended
Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Class of Stock [Line Items]
Total net transfers from the entity that is now a subsidiary of Navient	$ 0	$ 0	$ 0	$ 479,409,000
Common Stock
Class of Stock [Line Items]
Common stock closing price (usd per share)	$ 7.40		$ 7.40

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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